Family Materialize

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already flag destructiveHint=true and readOnlyHint=false, so mutation is known. The description adds meaningful specifics: it allocates item records and sequential part numbers, writes the registry back when absent, builds into the active document, and returns a defined result shape. This is richer than the annotation alone and does not contradict it.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured: purpose first, then behavior, modes, output, and parameter details. It is slightly dense with internal issue identifiers (#138, A1, #136, C1, #140) that do little to help an agent select or invoke the tool, but every substantive behavior is covered without bloat.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a tool with no output schema, the description still documents the return object's keys, the two modes, the active-document side effect, registry write-back, and all parameter meanings. Given the complexity of materializing an entire family, this is complete enough for correct invocation.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description carries the full burden, and it succeeds: table is specified as a .csv or .json path, registry as an optional items.json path with create-if-absent behavior, and mode as an optional override with the two accepted values. This adds real semantic meaning beyond the bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific verb and resource: 'Materialize a whole variant family from ONE design table.' It gives a concrete mental model ('make all the gears' becomes a table, not a loop) and distinguishes it from catalog and recipe operations. It is clearly different from related siblings like family_validate and standard_part_designate.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies when to use the tool—when you have a family table and want to materialize variants—and explains both modes. However, it never explicitly names an alternative tool or states when not to use this one. The usage context is present but the exclusion/alternative guidance is missing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.